Signal storage in telegraph printer systems



Aug. 17, 1943:,

J A. SPENQER SIGNAL STORAGE IN TELEGRAPH PRINTER SYSTEMS Filed Sept 17, 1940 2 Sheets-Sheet l INVENTOR. $40755 7. JPfA/CEP QTTOENEY 1943. J. A. SPENCER 2,327,075

SIGNAL STORAGE I N TELEGRAPH PRINTER SYSTEMS Filed Sept. 17, 1940 2 Sheet-Sheet 2 I Patented Aug. 17, 1943 SIGNAL STGRAGE IN TELEGRAPH PRINTER SYSTEMS James A. Spencer, Tcaneck, N. J., assignor to Radio Corporation of America, a corporation of Delaware Application September 17, 1940, Serial No.. 357,109

5 Claims;

It is an object of this invention to store the signals in a telegraph transmission system in single channel telegraphy to permit operation of the tape transmitter without consuming channel transmission time; 7

Other objects will appear in the iollowing description, reference being had to the drawings, in which:

Fig. 1 diagrammatically illustrates the transmission circuits of my invention.

Fig. 2 is a diagrammatic illustration of a tape transmitter for use in my invention.

Fig, 3 diagrammatically illustrates the circuits of my invention at the printing station claimed mi. se in my copending application, Ser. No. 395,334, filed May 27, 1941.

Referring to Figure 1, reference character HI represents generally the signal distributor having a ring and. a. commutator, while If indicates generally the distributor with a ring and a commutator for performing the local functions of the station.

Reference character t2 indicates diagrammatically the tape transmitter, which is of the A seven unit type. This tape transmitter is known in the art and is not specifically claimed herein.

In Figure 2 I have shown in moredetail this prior art transmitter. It consists of an operating magnet I3 having a pivoted armature l5. when: moved downwards extension H of this armature engages a lever 36 pivoted at IT and moves ratchet bar 08 upwards and causes the pivoted dog I!v to engage the teeth of a ratchet wheel 20 secured to a pinwhcel 2|. The pins, or teeth, of this wheel engage the driving holes in the perforated tape 22 and step it forward one code unit. Spring-pressed roller catch 21a holds this selection, The armature t5 also'operates the seeker bars 24 through an armature 'in detail in connection with Fig. 2.

29, which moves the contacts 35! against either a marking contact 3| or a spacing. contact 32, depending upon the positionofthe seeker bars. Spacing contacts in the switches for Nos. 5, 6 and 7 seeker bars are dead contacts, as shown in Fig. 1. Negative current for code units Nos. 5, 6 and 7 therefore does not derive from these switch points, but from back contacts of certain relays, as will later appear. I

The armature extension 23 has a wide enough end portion 33 to span the lugs 34 of all of the seeker bars, so that when the armature I5 is operated, it pulls all of the seeker bars downwards away from the tape before the lever 15 is engaged to move the tape, When the armature lever is released-by spring 34a. upon de-energization of the magnet, the spring 26 of each seeker bar immediately forces the seeker bar up till the pins 25 either engage the tape or pass through perforations therein. If there is no perforation in the tape for a seeker bar, its pin 25 will be stopped by the tape and the contact 30 wil} be inengagement with the spacing contact 32. It is held in this position by spring 3%. Thus, 3! are break contactsof magnet l3 and 32 are make contacts thereof It a perforation is adjacent the pin of a seeker bar, that seeker bar will be forced further upward by its spring 26 to the position shown in Fig. 2 and the switch lever 29 of that particular seeker bar will bring contact 30 against the marking contact 3!.

In the diagrammatic illustration in Fig. l, the switches 29 will be understood to move either against the spacing or the marking contacts, de-

pending upon the perforations, as just explained In my improvement, the tape transmitter for the seven unit type, spacing contacts Nos. 5, 6 and 7 are insulated from the negative bus bar 35, but contacts Nos. 1, 2, 3 and 4 are connected electrically thereto; All of the seven marking contacts are conductively connected to the positive bus bar 35.

The resistor-condenser network at 31 in various parts of the drawings is the well-known arrangement for reducing sparking at the switch contacts. This condenser-resistance network is connected from a contact through a resistance and condenser to ground.

The tongues of switches Nos.'1 to {i of the tape transmitter are connected to their corresponding segments in the commutator of the distributor 18. The tongues of switches,Nos.,5, 6 and '7 are,.however, not thus connected. They are connected to the operating coils of relays 38, 33 and 40, respectively. These relays each have break contacts between the negative terminal and their corresponding segment on the commu tator of distributor it).

When relay 38 is energized by the operating coil, its breal; contacts, connected to segment 5, are opened and two of it make contacts are closed. One of these connects the positive terminal to the holding coil 4| and to ground through the switch contact of relay 42, which is closed when this relay is de-energized. The other make contacts of relay 38 connect the positive terminal to segment No. of distributor l9.

Relay 39 likewise has switch contacts for energizing its holding coil 43 and connecting positive potential to its segment 6.

Relay 49 also has its holding coil 44 energized and its segment '7 connected to the positive terminal when its operating coil is energized.

The operating coils of relays 38, 39 and 49 are open at the contacts 47, 46 and 45 respectively of relays 48, so that they can not be energized until the relay 43 is energized. This relay 48 has its operating coil connected to segment No. 2, and preferably also to No. 3, on the commutator of distributor connected to segment No. 1 of this commutator.

The distributors I9 and Hare of a well-known construction, having brushes 49 and 59 rotating in unison to connect the distributor ring in succession to the seven contacts.

The ring of distributor in is connected to the outgoing link 59a for transmitting the signals to the receiving station.

The ring of distributor H is connected to the positive terminal. utor II are blank. Segments 5 and 6 are joined together and connected to the tape transmitter magnet I3, the other end of the magnet being connected to ground.

Ground, in the drawings, is understood to be circuit connections for accomplishing at the printer station functions similar to those accomplished at the transmitter station. The signals coming over the connecting link arrive at line 52 and energize the coils of polar relay 53, one end of the coil of this relay being connected to the line and the other end to ground. The marking contact on this polar relay is connected to the positive terminal and the spacing contact is a blank. The tongue of the relay 53 is connected to the ring of distributor 54. segment on the commutator of distributor 54 is connected through the coil of relay 55 to ground. The second and third segments are similarly connected to relay 56 and 5'! and ground.

Relay coil 55 has two switches, one connecting the positive terminal to the holding coil of the relay and thence to ground through the normally closed contact of relay 58. The other switch on relay 55 connects, when the relay is energized, segment 4 of the commutator of distributor 59 to one terminal of printer selector magnet No. 1, the other end being grounded. Relays 56 and 51 have switches for similarly closing their holding circuits, and switches for connecting segment 4 respectively through printer selector magnet No. 2 and No. 3 to ground.

Segments 4, 5, 6 and 7 of the commutator of distributor 54 are connected respectively to printer selector magnets Nos. 4, 5, 6 and 7.

The ring of distributor 59 is connected to the Relay 42 has its operating coil 3 Segments 4 and '7 of distrib- .2

positive terminal and segment No. 5 of the commutator of this distributor is connected through the operating coil of relay 58 to ground. Segment No. '7 of this commutator is connected to eighth pulse magnet No. 8 of the printer. All segments other than Nos. 4, 5 and 7 of distributor 59 are blank.

The printer intended to'be used in the embodiment of this application is a seven unit printer disclosed in my copending application, filed January 21, 1939, Serial No. 252,179, now Patent No. 2,274,103, granted Feb. 24, 1942. It is not necessary to complicate this disclosure by illustrating and describing this printer. It will be suflicient to say that the signal pulses operate the proper ones of selector magnets Nos. 1 to 7 and cause their armatures to engage their selector bars, and that the eighth pulse magnet No. 8 causes the selected selector bars to move and align notches therein with the proper type bar and immediately thereafter to energize the printing magnet for causing this bar to strike the type on the platen.

Distributors 54 and 59 have brushes 69, 6| for connecting their rings with the commutator segments, which run in synchronism with the brushes at the transmitter.

The operation of my improved printer system will now be described:

Referring to Fig. 1, let it be supposed that brushes 49 and 50 are on segments No. 5 of their respective distributors. It will also be assumed that this is the start of the signal operation. Positive current flows through brush 5!] and segment 5 of distributor l to tape transmitter magnet I3 and thence to ground. This moves the armature l5, which pulls all of the seeker bars 24 downwards to clear the pins from the tape and steps pinwheel 2| forward one notch (see also Fig. 2). This brings the perforations corresponding to the first code letter directly above the pins 25. While segment No. 5, in most cases, will be sufficient for the energization of the tape magnet, I find it advisable to connect this magnet also to segment No. 6, as shown.

When brushes 49 and 59 reach contact N0. 7, the tape magnet I3 is de-energized and the springs 26 move the seeker bars 24 upwards. Those positioned beneath a perforation will pass through, bringing their contact against marking contact 3|. Those that engage the tape because of the absence of a perforation do not move their switch arm 29 and consequently the spring 29a holds their contacts 39 against the space contacts 32.

Let it be assumed that perforations are punched in the tape at this point for the letter Y. This means that the pins 25 on the first, third and .sixth bar will pass through perforations in the tape and move contacts 30 downwards into engagement with the positive bus 3|. The contacts 30 of the switches of the remainder of the bars 24. namely Nos. 2, 4, 5 and 7, will be held by their springs against their corresponding space contacts.

. The code combination for the letter Y is now set up so that when the brushes 49 and 59 reach segments No. 1, a positive pulse is sent out over the connecting link a from distributor I0. At this time positive current passes through brush 59 of distributor H and the coil of relay 42 to ground, which opens the circuit of the holding 1 coils of relays 38', 39 and 40, if any of them had previously been energized, and releases them for new code combinations.

When brushes 49 and 5E) engage segment No. 2,

distributor HI, because the switch contact 30 is in engagement with the negative bus bar. At this time positive current flows through distributor II and the operating coil of magnet 48 to ground. Switches 55, 46 and 41 thus close. Current now flows through switch 45 and energizes the operating coil of relay 33. This switch closes its own holding circuit at once, as relay 42 was de-energized when brush 50- left segment .No. 1 ill-hen brushes 49 and 50 reach segment No. 3, positive current flows through distributor l to the connecting link 56a, because contact 35 on the transmitter tape mechanism is in engagement with the positive bus bar. Nothing additional happens in connection with the circuit of distributor II at this time, but it will be noted that the operating coil of relay 48 still remains energized because segments 2 and 3 are connected together.

' When brushes 4-9 and 59 engage segment No. 4, negative current is sent out to the connecting link 58a through distributor 10, because contact 35 in the tape mechanism is connected to the negative bus bar. Nothing happens at this time in connection with distributor I I.

When the brushes engage contacts No. 5, negative current cannot pass to the connecting link 50a from the tape transmitter contacts, because this contact is insulated from the negative bus bar, but it does pass thereto through the back contact of relay 38, now tie-energized. At this time positive current passes through the distributor H to segment No. 5 and energizes transmitter tape operating coil [3. seeker bars out of engagement with the tape and sets up a new combination by stepping the tape forward one code combination. It should be noted that code unit No. 6 previously selected is not destroyed, because relay 39 is energized and held in switch operative position by its holding coil &3. Thus, the No. 6 code unit became stored in relay 33, so that the, shift of the tape did not destroy the selection.

When the brushes 49 and 5G reach the sixth segment, a positive pulse is sent out, because of the energization of relay 39, as previously referred to. Magnet l3 still is energized, as segment No. 6 in distributor H is connected to segment No. 5.

When the brushes reach segment No. '7, negative current is sent out over connecting link 50a through the back contact of relay 45, now deenergized. Nothing happens at this time in connection with distributor ll.

All of the pulses for the selected code units for the letter Y have now passed out through the connecting link 55a and are received at the receiving station. A new code selection has also been set up, so that when the brushes start again on contacts No. 1, positive or negative pulses will be sent out for each signal, in accordance with this selection. At segment No. 2, the relay 39 will be cleared by momentary energization of relay 48.

It will thus be seen that with my invention I have stored pulses for the fifth, sixth and seventh positions in the tape transmitter prior to the transmission over the connecting link of the first unit of the selection. Thus, time is provided for setting up a new combination on the tape. This local function takes place during the time required for transmitting the fifth, sixth and seventh code unit from the storage means.

At the receiver (Fig. 3) the plus and minus This pulls the pins 25 of the pulses come in over line 52 and throw the tongue of polar relay 53 to the right with a positive pulse and to the left with a negative pulse.

With the code'combination. previously selected for the letter Y, a positive pulse would be received while brushes 6B and SI are on contacts No. 1 of the distributors. Positive current then. flows through brush 60 to the operating coil of relay 5!. Both of the switches of this relay then close. Positive current flows through the holding coil and the normally closed switch of relay 58 to ground. The other switch of this relay 5! is connected to contact No. 4 on distributor 59, so current cannot pass through this switch to the printer selector magnet 5| at this time. Nevertheless, the signal is stored in relay- 55.

When the brushes 60 and 6t reach segment No. 2 of their respective commutators, no current flows through'distributor 54, because a negative pulse is received and the switchtongue of polar relay 53 is in engagement with the left-hand blank contact.

When the brushes reach segment No. 3, positive current is coming in over line 52 and polar relay magnet 53 is energized to throw its switch tongue against the positive contact. This energizes relay 51', which closes the circuit of its holdmg coil through the normally closed contact of relay 58 and. connects the coil of printer magnet No, 3 to contact No. 4. The No. 3 printer mag.- net is not energized at this time, but the unit is merely stored in. relay 51.

When the brushes reach segment No. 4, no current passes through distributor 54, as a negative pulse is coming in over line 52'. However, brush 65 connects positive current to the switch, contacts of relays 55 and 51 and current imme.-. diately flows through the'closed switch contacts to magnets 1 and 3, to ground. The stored signals thus operate their respective magnets.

When the brushes reach segment No, 5, no current flows through distributor 54, because the incoming pulse is negative, .but the brush El on distributor 59 puts current through the operating coil of relay 58 and opens the hold-:- ing circuit of relays 55 and 5'5, thus returning them to their normal condition ready for the next code combination.

When the brushes reach segment No. 6, positive current is coming in over line 52 and current flows through brush on distributor 54 directly to printer magnet No. 6, thus completing the selection for the letter Y.

When the brushes reach segment No. 7, negative current is coming in over line 52 and no current passes through distributor 54, but current passes through brush 6| on distributor 59 to the No. S relay. This is commonly called the eighth pulse relay, which causes the printer selector bars to .be moved to the position demanded by the energization of printer selector magnets 1, 3 and 6. The performance of the printing function then takes place and it can continue, if necessary, during the time that the brushes are on the first, second and third segments of the distributors, because the signals for the first three printer selector magnets, if selected, will be stored in relays 55, 56 and 51 and do not require connection with printer selector magnets Nos. 1, 2 and 3 until the brushes reach the fourth segment of the distributors. Thus, at the receiver the storing of the first three units of the code combination gives ample time for the local printing function to take place and no time must be set aside for the performance of these functions.

In my invention it will be seen that all of the circuit time is used in transmitting signals and the local functions at both the transmitter and the receiver are performed While signals are being transmitted and received over the single channel.

Various changes in the embodiment of my invention may he made without departing from the spirit of my invention.

Having described my invention, what I claim 1s:

1. In a signaling system, a distributor having a plurality of commutator segments, a code transmitter having a plurality of switch arms, and switch contacts connected to a potential of one polarity,.means for moving said switch arms against said contacts, a plurality of relays each having an operating coil with one terminal connected to one of said switch arms and the other terminal adapted to be connected to a potential of opposite polarity, a switch tongue connected to one of said commutator segments, a make-con tact adapted to be connected to a potential 01 the first-mentioned polarity and a break contact connected to a potential of the second-mentioned polarity.

2. In a signaling system, a distributor having a plurality of commutator segments, a tape transmitter having a plurality of switch arms, and switch contacts connected to a potential of one polarity, seeker bars for moving said switch arms against said contacts, a plurality of relays each having an operating coil with one terminal connected to one of said switch arms and the other terminal adapted to be connected to a potential of opposite polarity, a switch tongue connected to one of said commutator segments, a make contact connected to a potential of the first-mentioned polarity and a break contact connected to a potential of the second-mentioned polarity.

3. In a signaling system for multi-unit edual length code units, a distributor commutator having a signaling segment for each unit in said code, a code transmitter having a switch arm for each code unit, one group of said switch arms having make and break contacts and another group having make contacts only, a relay for each switch arm of the second-mentioned group having a coil, a switch tongue and make and break contacts, a conductor connecting each switch arm of the first-mentioned group to a separate segment of said commutator, and a conductor connecting each of said tongues to separate segments of said commutator.

4. In a signaling system for multi-unit equal length code units, a distributor having a brush and a commutator with a signaling segment for each unit in said code, a code transmitter having a switch arm for each code unit, one group of said switch arms having make and break con tactsand another group having make contacts only, a relay for each switch arm of the secondmentioned group having a coil, switch tongue and make and break contacts, a conductor connecting each switch arm of the first-mentioned group to a separate segment of said commutator, a conductor connecting each of said tongues to separate segments of said commutator, a normally open electromagnetic switch in the circuit of the operating coils of said relays, and means for energizing the electromagnetic switch before said brush reaches the first of the last-mentioned segments.

5. In a signaling system for multiunit equal length code units, a distributor having a brush and a commutator with a signaling segment for each unit in said code, a code transmitter having a switch arm for each code unit, one group of said switch arms having make and break contacts and another group having make contacts only, a relay for each switch arm of the secondmentioned group having operating and holding coils, a switch tongue and make and break contacts, a conductor connecting each switch arm of the first-mentioned group to a separate segment of said commutator, a conductor connecting each of said tongues to separate segments of said commutator, a normally open electromagnetic switch in the circuit of the operating coils of said relays, means for energizing the electromagnetic switch before said brush reaches the first of the lastmentioned segments, and means for opening the circuit of said holding coils before the energizetion of aid electromagnetic switch.

JAMES A. SPENCER. 

